What are the Ideal Bone Grafting Materials to Use in Guided Bone Regeneration (GBR)? Many bone-grafting materials are available to the clinician when performing guided bone regeneration. Autogenous and allographic bone blocks, particulated allograft, synthetic bone grafts, particulated auto-geonous bone, and anorganic bovine-derived bone mineral (ABBM) are examples. 16 Bone blocks may be associated with varying degrees of morbidity depending on where they are harvested from. 13, 14, 15 Resorption may occur when using bone blocks, potentially compromising the outcome. 12, 18 Dr. Urban states, “Autogenous bone has three major qualities: 1) osteoconductive (providing a scaf-fold for bone formation), 2) osteogenic (containing mesenchymal cells), and 3) osteoinductive (contain-ing growth factors).” 16 A study investigated the proteins released from the extracellular matrix of cortical bone chips and 43 growth factors were identified, including several growth factors that are associated with bone formation. 17 ABBM is a deproteinized, sterilized, bovine cancel-lous bone that is osteoconductive and provides a favorable scaffold for bone formation. 16 “Studies have shown that a mixture of 1:1 ratio of autograft and ABBM to be highly efficacious in hori-zontal and vertical GBR and is the current standard for GBR procedures.” 16 Fig. 9 Fig. 10 How is Autogenous Bone Harvested? I use a Safescraper (Figs. 12-A, 13-B and 14-A) 3 to harvest bone for GBR procedures that do not require large amounts of autogenous bone. Generally, I harvest the bone from the external oblique ridge area on the mandibular ramus. A 20-30 mm incision paral-lel to the external oblique ridge in the mucosa approximately 3 mm away from the MGJ is made exposing the bone (Fig. 13-A). With long strokes the scraper collects the autogeonous bone in the reservoir (Figs.12-A, 13-B and 14-A), which is then emptied into a sterile dish (Fig. 14-B). The tissue site is closed with a continuous suture (Fig. 13-C). 5 An equal amount ABBM is placed in the sterile dish and mixed with the autogenous bone (Fig. 14-C). The ABBM I use is Bio-Oss small particle 0.25-1.0 mm cancellous granules from Geistlich. 3 The GBR procedure in this case is horizontal in nature. The bone mixture is placed on the decorticated labial bone surfaces of sites 7 (Fig. 15) and 10 (Fig. 16). Fig. 11 Fig. 12 What Membranes Do I Use When Performing GBR? One way to categorize membranes is whether they are resorbable or non-resorbable. www.orthodontics.com Winter 2018 35
Journal of the American Orthodontic Society Winter 2018: Page 35
